Device for connecting a wiper arm to a wiper blade and wiper arm and wiper blade using such a device

ABSTRACT

The invention relates to a device to connect a wiper arm ( 12 ) to a wiper blade ( 14 ) featuring a supporting element ( 16 ) holding a wiper strip ( 20 ) on which a base element ( 30, 60 ) is fastened as the first part of a coupling device, whereby the wiper arm ( 12 ) is embodied to be U-shaped and overlaps the base element ( 30, 60 ) with its U-shape and whereby holding means ( 42, 72 ) are embodied on the wiper arm ( 12 ) within its U-shape, which holding means form a second part of a coupling device and cooperate with the first part of the coupling device. It is proposed that the holding means ( 42, 72 ) be embodied as articulated means for holding the wiper blade ( 14 ) in an articulated manner, which can also transmit a bearing force ( 44 ) on the wiper blade ( 14 ) to be exerted by the wiper arm ( 12 ) on the wiper blade ( 14 ) in an operating position and which are at least approximately completely covered by the wiper arm ( 12 ).

STATE OF THE ART

The invention relates to a device to connect a wiper arm to a wiperblade. With known wiper blades of this type (EP0 753 439 A1), a wiperarm is divided into an inner wiper arm as well as an outer cap. Theinner wiper arm is composed in a conventional manner of a solid armsection and a spring-loaded articulated part linked to it, which extendsinto the area in which a wiper blade can be attached. The cap extendsover the wiper arm, the cap first supporting itself on a solid part ofthe wiper arm and secondly extending up to the end of the wiper blade inthe area above the linkage point for the wiper blade. The cap features aconnection for the wiper blade so that the wiper blade is fixed inposition. The bearing pressure from the wiper arm to the wiper blade istransmitted, however, by the extension of the inner wiper arm. Anintermediate piece is inserted for this providing the connection betweenthe wiper arm, cap and wiper blade, which requires an additional axisfor this. Due to the great number of individual parts, this structure isvery expensive for one and secondly not favorable for assembly.

ADVANTAGES OF THE INVENTION

The device in accordance with the invention has the advantage that thewiper arm is designed to be a single part and in the process takes onthe positioning of the wiper blade, transmission of the pendulum motionrequired for the wiper operation, transmission of the bearing pressureas well as formative elements. Fastened to the wiper blade is a baseelement, which takes on the task of the conventional axis and cooperatestogether with the wiper arm after the wiper arm and wiper blade havebeen connected. An intermediate part to secure or position theconnection is not required. As a result, the assembly and disassembly ofwiper arm and wiper blade is simple and quick both during initialassembly of the overall system as well as during subsequent replacementof the wiper blade by the end user.

The connection is designed particularly simply if the base elementfeatures at least two wings extending in the direction of the U-base ofthe wiper arm, said wings featuring counter holding means correspondingto the holding means in the sense of an articulated connection. The baseelement can be executed as a simple plate-bending stamped part that canbe manufactured cost effectively and can be fastened to a supportingelement of the wiper blade. This base element can be connectedpermanently and therefore captively to the wiper blade and assumes thefunction of the articulated axis of the wiper blade that is otherwisestandard and to be provided at additional expense.

Instead of an articulated axis, it is proposed that the counter holdingmeans be embodied as projections or openings. These then correspond withthe holding means of the wiper arm and thereby replace, as mentioned,the articulated axis that is otherwise standard.

If the holding means are embodied on the sides of the U-legs, it hasproved to be advantageous to provide projections for these. If the wiperarm is made of plastic, the projections can be formed simply, directlyon the inside of the U-legs using injection molding technology. Thesemeans of connection are not visible from the outside.

In addition to the holding means formed on the inside, additionalprojections can be attached that are adjacent to the wings of the baseelement in the assembly position and guide this element with a lowamount of play. This makes particularly quiet wiper operation possible.

Improved guidance is produced if the holding means are embodied ascounter wings extending at a distance from the U-legs, the counter wingsoverlapping with the wings of the base element in the assembly position.This produces a gap between the U-legs and the counter wings into whichthe wings of the base element can be inserted. Depending upon the widthof the gap, a certain play or a certain pressure can be generatedbetween the wings and the counter wings. For this reason the counterwings are embodied somewhat elastically so that they deflect andtherefore can accept tolerances.

The wiper blade can be clipped into or engage in the wiper arm verysimply if the holding means and/or the counter holding means featurebevels or roundings. It is also conceivable, however, for the holdingmeans or the counter holding means to feature openings with holes in thedirection of the counter holding means or holding means. These holescould have a narrowing, which then makes engaging in the correspondingprojections of the counter holding means or holding means possible.Under some circumstances, an axis can be advantageous instead ofprojections for this.

DRAWINGS

Two exemplary embodiments of the device in accordance with the inventionare depicted in the drawings and explained in more detail in thefollowing description. The drawings show:

FIG. 1 A wiper blade engaged in a wiper arm in a diagonal view,

FIG. 2 Wiper arm and wiper blade according to FIG. 1 in an unengagedposition,

FIG. 3 A view according to III in FIG. 2,

FIG. 4 A section along line IV—IV in FIG. 5 according to the secondexemplary embodiment,

FIG. 5 Along line V—V in FIG. 4 without a wiper blade,

FIG. 6 A base element according to the second exemplary embodiment in adiagonal representation and

FIG. 7 A view diagonally from below into a wiper arm according to thesecond exemplary embodiment.

The individual figures are not drawn using the same scale.

DESCRIPTION

FIG. 1 depicts a wiper system 10 with a wiper arm 12 and a wiper blade14. The wiper blade 14 features a supporting element 16, which iscomprised of two strips 18, which lie in longitudinal grooves of a wiperstrip 20. The longitudinal grooves are arranged in a head area 22 of thewiper strip 20, adjacent to a wiper wedge 26 featuring the wiper lip 24,which is connected with the head area 22 via a rocker bridge 28.

The wiper blade 14 in FIG. 1 is drawn in an extended form, as it occursfor example when the wiper blade 14 is guided over a very even window.In its relaxed shape that forms when lifted away from the window, thewiper blade 14 is bent in such a way that the wiper strip 20 lies in aconcave inner side of the supporting element 16. When placing the wiperblade 14 on a window, the ends of the wiper blade 14 thereby contactfirst the window and, once there is additional pressure, the entirewiper blade lies against the window. The supporting element 16 with thiskind of pre-bent shape thereby replaces the expensive support-bracketsystem of known bracket-mounted wiper blades.

A base element 30 also overlapping the head area 22 of the wiper strip20 is attached to the supporting element 16 (FIG. 2). The base elementfeatures a basic body 32, which bridges over the supporting element 16as well as the head area 22 of the wiper strip 20 and claws 34 areformed on its outer ends, which surround the strips 18 of the supportingelement 16 with a form fit. The base element 30 is also welded to thisform-fit with the supporting element 16, whereby a solid hold of thebase element 30 on the supporting element is guaranteed, on the onehand, and the strips 18 are held in the longitudinal grooves of thewiper strip 20, on the other hand.

Extending from the base body 32 of the base element 30 are two wings 36that extend away from the supporting element 16 approximately paralleland perpendicular to the base body 32. The base element 30 therebyrepresents a first part of a coupling device to connect the wiper bladeto the wiper arm.

The wiper arm 12 is designed to be U-shaped with a U-base 38, onto whichtwo U-legs 40 extending in the direction towards the wiper blade 14 areattached (FIG. 2). As shown in FIG. 1, the U-legs 40 completely overlapthe base element 30 in the assembly position between the wiper arm 12and wiper blade 14. Even in the longitudinal extension the wiper arm 12overlaps the base element 30. In FIGS. 1 and 2, the wiper arm 12 isguided only until shortly after the area of the connection to the wiperblade 14, but in another development it can also reach the end of wiperblade 14 thereby covering the wiper blade 14 completely.

Holding means 42 are embodied on the wiper arm 12 within its U-shape,which form a second part of a coupling device, and which cooperate withthe first part of the coupling device in the assembly position (FIG. 1).

The holding means 42 of wiper arm 12 cooperate with the wings 36 of thebase element 30 in the assembly position in such a way that the wiperblade 14 can twist relative to the wiper arm 12. The holding means 42are therefore articulated means for holding the wiper blade 14 in anarticulated manner. A bearing force 44 on the wiper blade 14 to beexerted by the wiper arm 12 on the wiper blade 14 in the operatingposition is transmitted via the holding means 42, which effect a fixingof position of the wiper blade 14 relative to the wiper arm 12. Thebearing force is generated by a spring that is not depicted here, whichis applied, on the one hand, to the wiper arm 12, thereby representing aspring-loaded articulated part, and to a solid arm section, on the otherhand.

A circular projection 46 is formed on each of the wings 36 of the baseelement 30, which extend towards one another, and are counter holdingmeans, which correspond to the holding means 42 in the sense of anarticulated connection. The holding means 42 are embodied in this regardas counter wings 48, which extend at a distance 50 essentially parallelto the U-legs 40. In the assembly position, the wings 36 of the baseelement 30 overlap with the counter wings 48 of the wiper arm 12. In theoverlapping region the projections 46 are arranged on the wings 36 sothat in the assembly position they project into the openings 52correspondingly arranged in the counter wings 48.

When assembling the wiper blade 14 that is already fastened to the baseelement 30 with the wiper arm 12, the wiper blade 14 is guided onto thewiper arm 12 from below until the wings 36 are adjacent to the counterwings 48. Then the wiper blade is moved perpendicular to itslongitudinal extension in the direction of the wiper arm 12 so that thewings 36 dip into the distances 50. As soon as the projections 46 reachthe area of the counter wings 48, the counter wings 48 deflect until theprojections 46 catch in the openings 42 when the wiper blade 14 isguided further up. The projections 46 are provided with bevels orroundings 54 in order to make deflection easier. Naturally, these canalso be provided on the lower end of the counter wings 48.

In a second exemplary embodiment according to FIGS. 4 through 7, thesame parts are provided with the same reference numbers.

FIG. 4 depicts a section of a wiper arm 12 holding a wiper blade 14 viaa coupling device. A base element 60 (FIGS. 4 and 6), which has aU-shape matching the inner contour of the wiper arm 12 with a U-base 62and U-legs 64, is fastened on the wiper blade 14. Attached to the U-legs64 are claws 66, which surround the strips 18 of the supporting element16 when the base element 60 is connected with the wiper blade 14. Alsoin this case the base element is welded to the supporting element.Projections 68 extending in the direction of the inside of the U-leg 40of the wiper arm 12 are attached to the U-legs 64, which, as seen fromthe claws 66, extend, like the wings 36, in the direction of the U-base38. The projections 68 feature central openings 70.

Projections 72, which project into the openings 70 of the base element60 in the assembly position, are formed on the insides of the U-legs 40that face one another. The projections 72 are smaller in their lateralextension than the openings 70 and are adjacent to the openings 70 onone side in the assembly position. The U-base 62 of the base element 60is removed in an area near the projections 68 and the U-legs 74 of thebase element 60 are raised in an arched manner in the direction of theU-base 38 of the wiper arm 12. In the assembly position, this results infreedom of movement of the wiper blade 14 against the wiper arm 12around a contact point between the inside edge of the opening 70 and theoutside edge of the projection 72, thereby preventing the base element60 from yielding because the U-legs 64 are adjacent to the U-base 38 ofthe wiper arm.

In order to keep lateral play to a minimum or to eliminate itcompletely, along with the projections 72, additional, strip-likeprojections 74 are formed on the insides of the U-legs 74.

For simpler assembly, the projections 72, which serve as holding means,feature bevels or roundings 76. If, when assembling the wiper blade, thebase element 60 is introduced between the U-legs from below, the U-legs40 deflect laterally until the projections 72 come to lie in theopenings 70.

While in the case of the first exemplary embodiment both localpositioning as well as transmission of the bearing force 44 take placebecause of the cooperation of the projections 46 with the openings 52,in the second exemplary embodiment, though positioning is achieved bythe cooperation of the openings 70 with the projections 72, transmissionof the bearing force 44 is achieved, however, by the cooperation of theU-base 38 with the base element's 60 U-legs 64 that continue in thedirection of the U-base 38.

It should still be mentioned that the described openings can be formedby molded cavities in individual cases, which makes it unnecessary torequire punching out actual holes during the manufacturing process.

A wiper arm 12 in accordance with the invention is characterized in thatit features a U-shape inside of which holding means are arranged, whichcan cooperate with counter holding means of the wiper blade. The holdingmeans are either embodied as counter wings 48, which extend from theU-base into the area encompassed by the U-shape, or as projections 72,which extend starting from the inside of the U-leg 40. It is alsoconceivable to provide both counter wings 48 as well as projections 72in combination on the inside of the U-legs 40.

A wiper blade according to the invention is characterized in that itfeatures a base element 30 or 60 overlapping a supporting element 16,which has wings 36 or equally acting U-legs 64 featuring projections 46or openings 70. These wings 36 and/or openings 70 are designed in such away that they cooperate with holding means 42 of a wiper arm 12 ascounter holding means and can provide an articulated connection.

1. A device connecting an elongated wiper arm to a wiper blade featuringa supporting element holding a wiper strip on which a base element isnon-rotatably fastened as the first part of a coupling device, wherebythe wiper arm is embodied to be U-shaped and overlaps the base elementwith its U-shape and whereby holding means are embodied as unitary withthe wiper arm within its U-shape, which holding means form a second partof a coupling device and cooperate with the first part of the couplingdevice, characterized in that the holding means is embodied asarticulated means for holding the wiper blade in an articulated manner,which can also transmit a bearing force on the wiper blade to be exertedby the wiper arm on the wiper blade in an operating position and whichis at least approximately completely covered by the wiper arm, whereinthe holding means is embodied as laterally spaced counter wingsextending at a distance from U-legs of the wiper arm, which counterwings overlap with and abut wings of the base element in an assemblyposition.
 2. Device according to claim 1, characterized in that the baseelement features at least two wings extending in the direction of aU-base of the wiper arm, wherein the wings of the base element featurecounter holding means corresponding to the holding means in the sense ofan articulated connection.
 3. Device according to claim 2, characterizedin that the counter holding means are projections or openings.
 4. Deviceaccording to claim 3, characterized in that the holding means areembodied as projections on facing sides of the U-legs of the wiper arm.5. Device according to claim 1, characterized in that along with theholding means additional projections are attached, which are adjacent towings of the base element in an assembly position.
 6. Device accordingto claim 1, characterized in that the wings extend between the U-legsand the counter wings in the assembly position.
 7. Device according toclaim 1, characterized in that the holding means and/or the counterholding means feature bevels or roundings.